Yes you can, but what you are describing fishing that type of water will replenish almost daily.
Yes you can overfish an area, but typically dock fish are resident fish and tend to reside there much of the year. Yes there will be exceptions and each lake and scenario is different but for the most part those are resident fish.
Try an experiment..... Run your docks as usual. Do a visual examination on the first fish you catch and find an identifying mark. Wait a couple of hours and run that same dock again and see if it bites again.
I have on many occasions caught the same fish within an hour or so.